# Author:  James Tam
# Version: Oct 2013

def fun (num): # Copy the value of 12 into a local variable
    print(num)  
    num = num + num # Only local copy changed
    print(num)  

def start():
    num = 12
    print(num)  # OK within scope
    fun(num)
    print(num) # Variable local to 'start' unchanged

start()